Spinal Cord Injuries (SCI)
Conditions
Keywords
spinal cord injury, transcutaneous spinal cord stimulation, rehabilitation
Brief summary
Spinal cord injury leads to long-lasting impairment, and currently, there is no cure for paralysis. Although transcutaneous spinal cord stimulation has shown promising results in recovering lost movements, its poor selectivity in muscle recruitment compared to invasive approaches limits the type of rehabilitation exercises that can be practiced. This project studies how spatial, frequency, and amplitude control of stimulation can be used to selectively target different neural pathways and muscle groups.
Detailed description
Spinal cord injury (SCI) is a life-altering event that leads to long-lasting motor impairment. Currently, there is no cure for paralysis. Transcutaneous spinal cord stimulation (tSCS) combined with exercise training can restore posture control, voluntary walking, and arm/hand function in people with SCI. However, its low selectivity in activating specific muscles compared to invasive approaches limits the rehabilitation exercises that can be practiced and help with recovery. This project will generate evidence-based knowledge of the neural mechanisms underlying spatial, frequency, and amplitude control of tSCS in generating different types of leg movements. Participants with SCI will perform leg movements using different stimulation parameter configurations in non-invasive tSCS. We will quantify changes in muscle recruitment, torque generation, and pain enabled by the different stimulation parameters. A clear understanding of the mechanisms by which these different parameters in non-invasive tSCS can be used to selectively target different muscle groups will promote the development of personalized therapies that directly target only those muscles that need assistance while respecting individuals' residual motor function.
Interventions
OTHERNo Stimulation
Participants complete motor tasks and outcome assessments with no spinal cord stimulation applied.
DEVICEConventional tSCS
Non-invasive transcutaneous spinal cord stimulation (tSCS) is delivered at 30 Hz using a single cathode electrode targeting the lumbar spinal cord to reinforce leg motor output during study tasks
DEVICESpatiotemporal tSCS
Stimulation parameters, including electrode location, stimulation frequency, and stimulation amplitude, are systematically varied to reinforce leg motor output during study tasks
Sponsors
Washington University School of Medicine
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
16 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
1. Age between 16 and 65 years. 2. Have a spinal cord injury (neurological level C3-T12) that occurred ≥1 year (chronic stage) prior to enrollment. 3. American Spinal Injury Association (ASIA) Impairment Scale (AIS) classification C or D 4. Able to voluntarily contract (motor score ≥ 1) at least two leg muscles (visual or palpable contraction). 5. Use of prescription medication(s) for control of spasticity has not changed in the last 2 weeks 6. Able to provide consent 7. Ability to follow multiple instructions and communicate pain or discomfort
Exclusion criteria
1. Progressive spinal lesions, including degenerative disorders of the spinal cord 2. Pregnant, planning to become pregnant, or currently breastfeeding 3. History of cardiopulmonary disease or cardiac symptoms 4. Implanted stimulators of any type (baclofen pump, epidural spinal stimulator, cardiac defibrillator, pace-maker, etc.) 5. Presence of orthopedic conditions that would negatively affect participation in leg exercise 6. History of autonomic dysreflexia that is severe, unstable, and/or uncontrolled 7. Unstable or significant medical conditions that can interfere with exercise or neurophysiological evaluations, such as severe neuropathic pain, depression, mood disorders, or other cognitive disorders 8. Spasms that limit the ability to participate in leg exercise activity 9. Breakdown in skin area that will be in contact with electrodes
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes in Torque | 30 minutes | The primary outcome is a measure of changes in voluntary torque production (Nm) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Muscle activation | 30 minutes | Muscle activation will be measured through electromyography as the peak-to-peak of the evoked responses (mV) |
| Pain/Nociception | 30 minutes | Pain will be evaluated using the Nociception Level (NOL) index during the different stimulation conditions. (Range: 0-100, 0 = no detectable nociceptive response, 100 = extreme nociceptive response) |
Countries
United States
Contacts
CONTACTIsmael Seáñez, PhD
CONTACTCarolyn Atkinson, BS
Outcome results
None listed